The United States would derive no meaningful military benefit from increased use of alternative fuels to power its jets, ships and other weapons systems, according to a government-commissioned study by the RAND Corporation scheduled for release Tuesday.

Well, that’s actually pretty obvious. Nobody argues that jets run better on fuel blended with liquids derived from animal waste, seed plants, or algae. Nor do defense planners worry that oil supply disruptions would force the U.S. military to mothball aircraft, ships, or other weapons platforms for lack of home-grown biofuel.

The RAND study [p. 12] goes further:

Ethanol and biodiesel are unsuitable for use in weapon systems. They pose a severe safety risk, reduce performance, unduly complicate fuel delivery and storage, and generate maintenance problems.

The bigger problem, though, as Zeller puts it, is that “most alternative-fuel technologies [are] unproven, too expensive or too far from commercial scale to meet the military’s needs over the next decade.”

This is not exactly the message one hears from top military brass. For example, on Earth Day 2010, Navy Secretary Ray Mablus crowed about the Navy’s experimentation with jet fuel blended from petroleum and camelina (a non-edible plant). Mablus neglected to mention the cost: $65 per gallon — about 30 times more expensive than commercial aviation fuel. (For more details, see “Bio Jet Fuel: the Real $600 Toilet Seat?“)

The U.S. Armed Forces, or at least the Navy and Air Force, may be too bullish on biofuels to give the RAND report a fair shake. Too bad for us taxpayers. The Air Force, says RAND, ”aims to be prepared by 2016 to acquire amounts of alternative fuel blends sufficient to meet 50 percent of its domestic requirements for aviation fuel. Air Force policy clearly specifies that this must be done in a manner that is cost-competitive and emits fewer greenhouse gases than fuels produced from conventional petroleum. Moreover, the alternative fuel component of the blend must be derived from domestic sources.”

Similarly, RAND reports, “In October 2009, Navy Secretary Ray Mabus committed the Navy and Marine Corps to “creating a Green Strike Group composed of nuclear vessels and ships powered by biofuels” by 2012 and deploying it by 2016. By 2020, at least 50 percent of the energy the Navy consumes is to come from alternative sources.”

These goals probably won’t be met, and can’t be met at reasonable cost: “It is highly uncertain whether appreciable amounts of hydrotreated renewable oils [alternative fuels derived from animal fats, waste, and vegetable matter] can be affordably and cleanly produced within the United States or abroad.” RAND estimates [p. xii] that the “available supply” of animal fats and waste oils “will likely limit production to no more than 30,000 barrels per day.” For perspective, the Department of Defense consumes about 337,000 barrels per day (bpd) of petroleum-based fuel [p. 6]; the U.S. economy consumes about 19 million bpd of petroleum-based fuel.

Jatropha and camelina are often mentioned as ideal plants to meet these requirements, but there exists little evidence to back these claims. Even if low-greenhouse-gas approaches can be established and verified, total fuel production is likely to be limited. Producing just 200,000 barrels per day (about 1 percent of U.S. petroleum consumption) would require an area equal to about 10 percent of the croplands currently under cultivation in the United States. [p. xii]

Many tout algae-based biofuel as the next big thing. However, “Because all methods for liquid fuel production from algae are at early stages of development, lifecycle greenhouse gas emissions for commercially produced algae-derived fuels remain uncertain.” [p. 30] In addition, ”the commercial prospects of this approach remain highly uncertain.” [p. 78]

The RAND study concludes:

Considering (1) the very limited production potential for fuels derived from animal fats and waste oils, (2) the highly uncertain prospects for affordable, lowgreenhouse-
gas fuels derived from seed crops, and (3) the early development status of algae-based concepts, hydrotreated renewable oils do not constitute a credible, climatefriendly
option for meeting an appreciable fraction of military fuel needs over the next decade. Because of limited production potential, fuels derived from animal fats, waste
oils, and seed oils will never have a significant role in the larger domestic commercial marketplace. Algae-derived fuels might, but technology development challenges suggest
that algae-derived fuels will not constitute an important fraction of the commercial fuel market until well beyond the next decade.